Download Stroom et al. Int J Radiat Oncol Biol Phys 2007

The use of Radiotherapy in
Cancer.
What is radiotherapy?
The treatment of cancer with ionising radiation is called
Radiotherapy or Radiation Oncology.
Radiotherapy is one of three main disciplines within the
science of oncology.The other two disciplines are
surgery and chemotherapy.
Radiotherapy is a clinical science, with clinical, physical
(radiophysics) and biological (radiobiology) aspects.
What is Radiotherapy- Radiation Oncology (RT)?
BIOLOGY
CLINIC
1. Tumour
2. Normal tissue
RT
PHYSICS
The three “C” of radiation
Oncology
- “C” for cure
- “C” for cheap
- “C” for conservative treatment
Treatment of solid cancers
100 new cases
Skin & in situ
cervical ca. (30)
Localised & operable (48)
Cured by surgery and/or
radiotherapy (30)
Advanced (22)
Relapsed (18)
Candidates for chemotherapy (40)
Potentially curable (5)
Cured by
chemotherapy (2)
Incurable (35)
Possible
life prolongation (10)
“C” for cheap
The total costs for radiotherapy are only 5 % of the
total costs for cancer treatment in Sweden and in the
European Community.
Swedish Council of Medical Technology Assessment in Healthcare, EC.
“C” for conservative
treatment
- Breast
- Larynx
- Rectum, Anal canal
- Bladder
- Penis
-Eye…
NB: Non exhaustive list
Radiotherapy tackles all hallmarks of cancer
Solimini et al. Cell 2007
Reduce the number of tumour cells to be killed by e.g.
surgery
Doublings
Cells
Grams
The problem
Tumour control
Effect
100%
Normal tissue damage
Tumour Dose
Increase the therapeutic ratio
Effect
Tumour control
Tumour Dose
Normal tissue damage
Increase the therapeutic ratio
Effect
100%
Tumour control
Tumor Dose
Normal tissue damage
Integration of chemotherapy and radiotherapy
40
35
5-year survival (%)
30
25
20
15
10
0
20
40
60
80
100
120
140
SER (days)
D. De Ruysscher et al. J Clin Oncol 2006
160
180
The four parts of radiotherapy
Lokalisatie
Bestraling en verificatie
Intekening doelvolume
en gezond weefsel
Treatment planning
Delineation of the target volumes and the normal tissues
liver
skin
stomach
target volume
heart
heart
liver
left kidney
stomach
target volume
target
volume
pancreas
pancreas
skin
liver
skin
Patient modelling in 3D
heart
liver
stomach
alvleesklier
target
volume
spleen
right kidney
spinal cord
left kidney
3-D patient model
Problem
Do nothing?
 Large systematic error
4 3
Radius and volume ( r  )
3
A (small) reduction of
the margin (5 mm)
leads to a 50 %
reduction of the
volume
Volume peel = volume flesh
Verellen D et al. Nature Rev Cancer 2007
Manual PET-CT contouring
Automatic PET-CT contouring
+ manual editing
van Baardwijk et al. Int J Radiat Oncol Biol Phys 2007
I
Automatic contouring
of tumors on the
basis of 4D-FDGPET-CT scans:
Correlation with
pathology
x
x
J
Stroom et al. Int J Radiat Oncol Biol Phys 2007
K
Treatment planning
• Bepaling bestralingsrichtingen (bundels) met
optimalisatie van:
- bundelenergie
- bundelrichting
- bundeldosis
- bundelgrootte en -vorm
Dosisverdeling
Dose-Volume Histogram (DVH)
target
volume
heart
zonder aanpassing
Radiotherapy using CT-PET, e.g.: lung cancer with
atelectasis
What is radiotherapy?
The treatment of cancer with ionising radiation is called
Radiotherapy or Radiation Oncology.
Radiotherapy is one of three main disciplines within the
science of oncology.The other two disciplines are
surgery and chemotherapy.
Radiotherapy is a clinical science, with clinical, physical
(radiophysics) and biological (radiobiology) aspects.